Intraocular lenses are widely used to be replaced with human opacity crystalline lenses in cataract treatments or normal human crystalline lenses for compensating the optical powers of the lenses. In intraocular lens insertion surgeries for the cataract treatments, a discission wound which is several millimeters in length is produced at the edge of the cornea, the human crystalline lens is crushed and removed by phacoemulsification and aspiration etc. and the intraocular lens is inserted and fixed in the eye, for example.
Polymethyl methacrylate (PMMA), acrylic resin, silicon resin etc. are used as the material of the intraocular lens. The structure of the intraocular lens can be divided into an optical member and a supporting member. The intraocular lens is enclosed in a dedicated intraocular lens insertion apparatus. When the intraocular lens is used, the intraocular lens insertion apparatus is taken out from the package of the apparatus in an aseptic manner, and the tip of the insertion apparatus is inserted into the eye from the discission wound and the insertion apparatus is handled to guide the intraocular lens into the human crystalline lens capsule.
It is desirable that the discission wound be as small as possible in order to mitigate the burden of the patient. Therefore, the insertion apparatus is configured to eject the intraocular lens into the eye in a folded state.
For example, patent document 1 discloses a structure in which the opening of the tip of the insertion apparatus is configured to have an oblique surface oblique to the longitudinal direction of the opening. In addition, a roof is provided for the tip of the opening. The roof functions to open the wound when the tip of the insertion apparatus is inserted into the wound. Further, patent document 2 discloses a structure in which the end surface of the opening of the tip of the insertion apparatus is formed in a curved shape. Therefore, the possibility that the insertion apparatus unnecessarily stimulates the eye tissues can be reduced since the opening in the curved shape can make a smooth contact with the wound etc. when the tip of the insertion apparatus is inserted into the wound.